Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thu nang » thi nang, thu hang, thu bang
vanh dai » van dai, vanh tai, lanh dao
hanh dai » hanh tai, hanh dao, thanh dat
te sach » toc sach
cuu tre » cua tre, cau tren, cau treo
hieu va » lieu va, hieu qua
tuc va » thuc va, truc va, tuc xa
luc va » duc va, loc va
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: te sach thu nang x hoi. hieu va cac ((luc va) OR (tuc va)) ((hanh dai) OR (vanh dai)) cuu tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach thu nang x hoi. hieu va cac ((luc va) OR (tuc va)) ((hanh dai) or (vanh dai)) cuu tre~".
• Adding a wildcard symbol may retrieve word variants: te sach thu nang x hoi. hieu va cac ((luc va) OR (tuc va)) ((hanh dai) or (vanh dai)) cuu tre*.